Write to cache

[tt.git] / tt

diff --git a/tt b/tt
index ecafb5c..840a8e5 100755 (executable)
--- a/tt
+++ b/tt
@@ -4,6 +4,9 @@
 ; TODO optional text wrap
 ; TODO write
 ; TODO caching (use cache by default, unless explicitly asked for update)
+; - [x] value --> cache
+; - [ ] value <-- cache
+;   requires: commands
 ; TODO timeline limits
 ; TODO feed set operations (perhaps better done externally?)
 ; TODO timeline as a result of a query (feed set op + filter expressions)
@@ -37,15 +40,17 @@
 
 #lang racket
 
+(require openssl/sha1)
 (require racket/date)
 
 (require http-client)
 (require rfc3339-old)
 
-(struct msg  (tm_epoch tm_rfc3339 nick uri text))
+(struct msg  (ts_epoch ts_rfc3339 nick uri text))
 (struct feed (nick uri))
 
 (define (concurrent-filter-map num_workers f xs)
+  ; TODO switch from mailboxes to channels
   (define (make-worker id f)
     (define parent (current-thread))
     (λ ()
@@ -72,12 +77,9 @@
                             [(cons x xs) (begin
                                            (thread-send thd (cons 'unit x))
                                            (dispatch ws xs ys))])])))
-  (define workers
-    (range 1 (add1 num_workers)))
-  (define threads
-    (map (λ (id) (thread (make-worker id f))) workers))
-  (define results
-    (dispatch workers xs '()))
+  (define workers (range num_workers))
+  (define threads (map (λ (id) (thread (make-worker id f))) workers))
+  (define results (dispatch workers xs '()))
   (for-each thread-wait threads)
   results)
 
@@ -87,7 +89,7 @@
       ['single-line "~a  \033[1;37m<~a ~a>\033[0m  \033[0;~am~a\033[0m~n"]
       ['multi-line  "~a~n\033[1;37m<~a ~a>\033[0m~n\033[0;~am~a\033[0m~n~n"]
       [_           (raise (format "Invalid output format: ~a" out-format))])
-    (date->string (seconds->date [msg-tm_epoch msg]) #t)
+    (date->string (seconds->date [msg-ts_epoch msg]) #t)
     (msg-nick msg)
     (msg-uri  msg)
     (if odd 36 33)
@@ -108,17 +110,17 @@
           (log-warning "Invalid msg line from nick:~a, msg:~a" nick str)
           #f)
         (let*
-          ([tm_rfc3339 (list-ref toks 0)]
-           [tok_text   (list-ref toks 1)]
-           [t (string->rfc3339-record tm_rfc3339)]
+          ([ts_rfc3339 (first  toks)]
+           [text       (second toks)]
+           [t          (string->rfc3339-record ts_rfc3339)]
            ; TODO handle tz offset
-           [tm_epoch (find-seconds [rfc3339-record:second t]
+           [ts_epoch (find-seconds [rfc3339-record:second t]
                                    [rfc3339-record:minute t]
                                    [rfc3339-record:hour   t]
                                    [rfc3339-record:mday   t]
                                    [rfc3339-record:month  t]
                                    [rfc3339-record:year   t])])
-          (msg tm_epoch tm_rfc3339 nick uri tok_text))))))
+          (msg ts_epoch ts_rfc3339 nick uri text))))))
 
 (define (str->lines str)
   (string-split str (regexp "[\r\n]+")))
@@ -126,6 +128,12 @@
 (define (str->msgs nick uri str)
   (filter-map (λ (line) (str->msg nick uri line)) (str->lines str)))
 
+(define (hash-sha1 str)
+  (define in (open-input-string str))
+  (define digest (sha1 in))
+  (close-input-port in)
+  digest)
+
 (define (uri-fetch uri)
   (log-info "GET ~a" uri)
   (define resp (http-get uri))
@@ -134,7 +142,18 @@
   (log-debug "finished GET ~a status:~a  body length:~a"
              uri status (string-length body))
   ; TODO Handle redirects
-  (if (= status 200) body (raise status)))
+  (if (= status 200)
+    (let*
+      ([url-digest
+         (hash-sha1 uri)]
+       [cache-file-path
+         (expand-user-path (string-append "~/.tt/cache/" url-digest))])
+      (display-to-file
+        body cache-file-path
+        #:exists 'replace)
+      body)
+    ; TODO A more-informative exception
+    (raise status)))
 
 (define (timeline-print out-format timeline)
   (for ([msg timeline]
@@ -166,14 +185,12 @@
 ; TODO timeline contract : time-sorted list of messages
 (define (timeline num_workers feeds)
   (sort (append* (concurrent-filter-map num_workers feed->msgs feeds))
-        (λ (a b) [< (msg-tm_epoch a) (msg-tm_epoch b)])))
+        (λ (a b) [< (msg-ts_epoch a) (msg-ts_epoch b)])))
 
 (define (str->feed str)
   ; TODO validation
   (define toks (string-split str))
-  (feed
-    [list-ref toks 0]
-    [list-ref toks 1]))
+  (apply feed toks))
 
 (define (str->feeds str)
   (map str->feed (str->lines str)))
@@ -204,14 +221,16 @@
   (define user-agent
     (let*
       ([prog-name      "tt"]
-       [prog-version   "0.3.0"]
+       [prog-version   "0.3.4"]
+       [prog-uri       "https://github.com/xandkar/tt"]
        [user-feed-file (expand-user-path "~/twtxt-me.txt")]
-       [user           (list-ref (file->feeds user-feed-file) 0)])
-      (format "~a/~a (+~a; @~a)"
-              prog-name
-              prog-version
-              (feed-uri user)
-              (feed-nick user))))
+       [user
+         (if (file-exists? user-feed-file)
+           (let ([user (first (file->feeds user-feed-file))])
+             (format "+~a; @~a" (feed-uri user) (feed-nick user)))
+           (format "+~a" prog-uri))]
+       )
+      (format "~a/~a (~a)" prog-name prog-version user)))
 
   (setup-logging)
   (current-http-response-auto #f)